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    <title>rcond</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>rcond</b> -   inverse condition number</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>rcond(X)   </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>X</b>
        </tt>: real or complex square matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>rcond(X)</b>
      </tt> is an estimate for the reciprocal of the
    condition of <tt>
        <b>X</b>
      </tt> in the 1-norm.</p>
    <p>
    If <tt>
        <b>X</b>
      </tt> is well conditioned, <tt>
        <b>rcond(X)</b>
      </tt> is close to 1.
    If not, <tt>
        <b>rcond(X)</b>
      </tt> is close to 0.</p>
    <p>
      <tt>
        <b>[r,z]=rcond(X)</b>
      </tt> sets <tt>
        <b>r</b>
      </tt> to
    <tt>
        <b>rcond(X)</b>
      </tt> and returns <tt>
        <b>z</b>
      </tt> such that
    <tt>
        <b>norm(X*z,1) = r*norm(X,1)*norm(z,1)</b>
      </tt>
    </p>
    <p>
    Thus, if <tt>
        <b>rcond</b>
      </tt> is small <tt>
        <b>z</b>
      </tt> is a vector in the kernel.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

A=diag([1:10]);
rcond(A)
A(1,1)=0.000001;
rcond(A)
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="svd.htm">
        <tt>
          <b>svd</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="cond.htm">
        <tt>
          <b>cond</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="inv.htm">
        <tt>
          <b>inv</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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